Hydrogen sulfide production process and related reactor vessels

ABSTRACT

The present invention discloses a hydrogen sulfide reactor vessel with an external heating system that is conductively and removably attached to an exterior portion of the reactor vessel. Also disclosed are processes for producing hydrogen sulfide utilizing the reactor vessel.

This application is a continuation application of PCT internationalpatent application PCT/US2015/065071, now WO 2017/099783, filed on Dec.10, 2015, the disclosure of which is incorporated herein by reference inits entirety.

FIELD OF THE INVENTION

The present disclosure concerns reactor vessels for the production ofH₂S, and more particularly relates to heating systems for reactorvessels containing liquid sulfur.

BACKGROUND OF THE INVENTION

There are various techniques that can be used to heat and maintain areactor vessel containing liquid sulfur at an appropriate start-up andsteady-state operating temperature. However, known techniques havedrawbacks due to the corrosive nature of the reactor contents, as wellas the extreme temperature range encountered during a production cycle(from start-up to steady-state production to shutdown), which can oftenspan a temperature range of 500° C. or more. Therefore, it would bebeneficial to have reactor vessels with improved heating systems formore efficient and long-term operation. Accordingly, it is to these endsthat the present disclosure is directed.

SUMMARY OF THE INVENTION

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the detaileddescription. This summary is not intended to identify required oressential features of the claimed subject matter. Nor is this summaryintended to be used to limit the scope of the claimed subject matter.

Various H₂S reactor vessels are described herein. In one embodiment, theH₂S reactor vessel can comprise (a) a reaction chamber comprising areactor wall, the reaction chamber configured to contain liquid sulfur;(b) a reactor inlet for liquid sulfur, the reactor inlet positioned atan upper portion of the reactor vessel; (c) a reactor outlet for liquidsulfur, the reactor outlet positioned at a lower portion of the reactorvessel; (d) a gas inlet for a hydrogen-containing gas, the gas inletconnected to a gas distributor, the gas distributor positioned above thereactor outlet for liquid sulfur and configured to inject thehydrogen-containing gas into the liquid sulfur in the reaction chamber;(e) a gas outlet for a H₂S-rich gas stream, the gas outlet positionedabove the reactor inlet; (f) an internal heating system, the internalheating system positioned in the liquid sulfur in the reaction chamberduring continuous operation of the reactor vessel and configured tomaintain an operating temperature above the melting point of sulfur; and(g) an external heating system comprising a heated reactor conduitconductively and removably attached to a portion of an exterior surfaceof the reactor wall, wherein at least a portion of the heated reactorconduit is positioned in close proximity to the internal heating systemand is configured to maintain a start-up temperature of the liquidsulfur above the melting point of sulfur at least until a level of theliquid sulfur in the reaction chamber is above the internal heatingsystem. The standard melting point of sulfur is approximately 115.2° C.

Embodiments of this invention also are directed to a reactor vesselfurther comprising a quench column, generally positioned above theinternal heating system and below the reactor inlet for liquid sulfur,in which the external heating system further comprises a heated columnconduit conductively and removably attached to a portion of an exteriorsurface of the quench column. The heated column conduit can beconfigured to maintain a quench column operating temperature of theliquid sulfur in the quench column above the melting point of sulfur.

H₂S production processes also are disclosed herein. Generally, theseprocesses can comprise (i) controlling a reaction chamber containingliquid sulfur at a start-up temperature above the melting point ofsulfur with an external heating system comprising a heated reactorconduit conductively and removably attached to a portion of an exteriorsurface of the reaction chamber; (ii) adding liquid sulfur to thereaction chamber to a level sufficient to immerse an internal heatingsystem positioned within the reaction chamber; (iii) engaging theinternal heating system to reach and maintain an operating temperatureof the liquid sulfur of at least about 300° C.; (iv) adding ahydrogen-containing gas into the liquid sulfur and reacting to produceH₂S; and (v) optionally, discontinuing the operation of the externalheating system.

Both the foregoing summary and the following detailed descriptionprovide examples and are explanatory only. Accordingly, the foregoingsummary and the following detailed description should not be consideredto be restrictive. Further, features or variations may be provided inaddition to those set forth herein. For example, certain embodiments maybe directed to various feature combinations and sub-combinationsdescribed in the detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this disclosure, illustrate various embodiments of the presentinvention. In the drawings:

FIG. 1 is a partial cross-sectional view of a H₂S reactor vessel in anembodiment of the present invention.

FIG. 2 is a front perspective view of the bottom section of the reactorvessel of FIG. 1, with a representative external heating system, withsome parts omitted for clarity.

FIG. 3 is a close-up side perspective view of the bottom section of thereactor vessel of FIG. 1, with a representative external heating system,with some parts omitted for clarity.

FIG. 4 is a front perspective view of the top section of the reactorvessel of FIG. 1, with a representative quench column and externalheating system, with some parts omitted for clarity.

FIG. 5 is a close-up cross-sectional view of a portion of the externalheating system illustrated in FIGS. 2-4.

DEFINITIONS

To define more clearly the terms used herein, the following definitionsare provided. Unless otherwise indicated, the following definitions areapplicable to this disclosure. If a term is used in this disclosure butis not specifically defined herein, the definition from the IUPACCompendium of Chemical Terminology, 2^(nd) Ed (1997), can be applied, aslong as that definition does not conflict with any other disclosure ordefinition applied herein, or render indefinite or non-enabled any claimto which that definition is applied. To the extent that any definitionor usage provided by any document incorporated herein by referenceconflicts with the definition or usage provided herein, the definitionor usage provided herein controls.

Herein, features of the subject matter are described such that, withinparticular aspects and/or embodiments, a combination of differentfeatures can be envisioned. For each and every aspect, and/orembodiment, and/or feature disclosed herein, all combinations that donot detrimentally affect the designs, processes, and/or methodsdescribed herein are contemplated with or without explicit descriptionof the particular combination. Additionally, unless explicitly recitedotherwise, any aspect, and/or embodiment, and/or feature disclosedherein can be combined to describe inventive features consistent withthe present disclosure.

While apparatuses, systems, and processes are described herein in termsof “comprising” various components, devices, or steps, the apparatuses,systems, and processes can also “consist essentially of” or “consist of”the various components, devices, or steps, unless stated otherwise.

The terms “a,” “an,” and “the” are intended to include pluralalternatives, e.g., at least one. For instance, the disclosure of “aconduit” or “a reactor outlet” is meant to encompass one, orcombinations of more than one, conduit or reactor outlet, unlessotherwise specified.

Various numerical ranges are disclosed herein. When a range of any typeis disclosed or claimed, the intent is to disclose or claim individuallyeach possible number that such a range could reasonably encompass,including end points of the range as well as any sub-ranges andcombinations of sub-ranges encompassed therein, unless otherwisespecified. As a representative example, the present disclosure recitesthat an operating temperature of a reactor vessel can be in a range fromabout 350° C. to about 600° C. in certain embodiments. By a disclosurethat the temperature can be in a range from about 350° C. to about 600°C., the intent is to recite that the temperature can be any temperaturewithin the range and, for example, can be equal to about 350° C., about400° C., about 450° C., about 500° C., about 550° C., or about 600° C.Additionally, the temperature can be within any range from about 350° C.to about 600° C. (for example, the temperature can be in a range fromabout 400° C. to about 550° C.), and this also includes any combinationof ranges between about 350° C. and about 600° C. Likewise, all otherranges disclosed herein should be interpreted in a manner similar tothis example.

Although any methods, devices, and materials similar or equivalent tothose described herein can be used in the practice or testing of theinvention, the typical methods, devices, and materials are hereindescribed.

All publications and patents mentioned herein are incorporated herein byreference for the purpose of describing and disclosing, for example, theconstructs and methodologies that are described in the publications andpatents, which might be used in connection with the presently describedinvention.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description refers to the accompanying drawings.Wherever possible, the same or similar reference numbers are used in thedrawings and the following description to refer to the same or similarelements or features. While various embodiments of the invention aredescribed, modifications, adaptations, and other implementations arepossible. For example, substitutions, additions, or modifications can bemade to the elements illustrated in the drawings, and the methodsdescribed herein can be modified by substituting, reordering, or addingstages to the disclosed methods. Accordingly, the following detaileddescription and its exemplary embodiments do not limit the scope of theinvention.

As disclosed herein, the reactor vessels with a removable externalheating system offer several advantages and benefits over existingreactor vessels containing an internal steam coil (i.e., within thereaction chamber). First, if repairs are needed with an internal steamcoil, the reactor has to be shutdown and cleared of any reactorcontents, including sulfur and H₂S, in order to prevent any harmfulexposure. In contrast, the external heating system of the disclosedreactor vessels can contain a steam circuit, but the piping is outsideof the reactor vessel, so access and repairs are much easier. Second,significant corrosion issues exist with an internal steam coil, andexotic metallurgy is often required. The environment inside the reactionchamber can cause significant corrosion due to sulfur and H₂S attemperatures in excess of 400° C., so corrosion-resistant stainlesssteel alloys may be required in order to prevent frequent reactorshutdowns and repairs due to corrosion. However, stainless steel-basedinternal heating coils do not conduct heat well, due to poor thermalconductivity. In contrast, the external heating system of the disclosedreactor vessels does not require exotic metallurgy nor corrosionresistance; in fact, material/metal selection for piping used in theexternal heating system can be specifically designed for efficient heattransfer performance. Third, a reactor vessel with an internal steamcoil is costly and difficult to fabricate due to the heating coil andrelated connections that must pass through the reactor walls. Incontrast, the external heating system of the disclosed reactor vesselsrequires no additional fabrication concerns for the reactor vessel,other than inclusion (if desired) of simple attachment points on theexterior surface of the vessel to facilitate easy fastening of portionsof the heating system. Fourth, temperature control with an internalheating coil can be problematic due to fouling or build-up on the coilsurfaces (the cleaning of which may require a reactor shutdown) and dueto the inability to prevent liquid sulfur solidification on the interiorwalls of the reaction chamber. In contrast, the external heating systemof the disclosed reactor vessels provides heat directly to the reactorwalls to prevent liquid sulfur solidification, and if any fouling orbuild-up concerns occur with the external heating system, the reactorvessel does not need to be opened or shutdown.

In addition, the disclosed reactor vessels with a removable externalheating system offer benefits over comparable reactor vessels with aheating jacket or steam jacket surrounding the exterior surface. Due tothe extreme temperature ranges encountered during production cycles(from start-up to steady-state production to shutdown), often spanning500° C. or more, jacketed heating systems cannot withstand the thermalexpansion and contraction of the reaction chamber (e.g., using stainlesssteel) and would fail accordingly. In contrast, the external heatingsystem of the disclosed reactor vessels is capable of withstanding thethermal expansion and contraction of the reaction chamber (e.g., usingstainless steel) encountered during production cycles over largetemperature ranges. As would be recognized by those of skill in the art,additional advantages and benefits to the disclosed reactor vessels arereadily apparent from this disclosure.

Hydrogen Sulfide Reactor Vessels

FIG. 1 illustrates an embodiment of a H₂S reactor vessel 110 consistentwith the present invention. While not being limited thereto, the H₂Sreactor vessel 110 is described herein as it pertains to its use in aGirdler process for non-catalytically producing H₂S from sulfur and H₂,or alternatively, as it pertains to the reaction of methane and sulfurto produce H₂S and CS₂. The H₂S reactor vessel 110 in FIG. 1 can includea reaction chamber 115 having a reactor wall 105, an internal heatingsystem 180, and a gas distributor 150. The reactor vessel 110 canfurther include a liquid sulfur inlet 120, a liquid sulfur outlet 160, ahydrogen-containing gas inlet 130 connected to the gas distributor 150,and a H₂S-rich gas outlet 170. The arrows in FIG. 1 illustrate typicalflow paths or directions for the respective inlet/outlet streams. TheH₂S reactor vessel 110 is illustrated with liquid sulfur 140 present atthe representative liquid sulfur level 145 shown in FIG. 1. Thehydrogen-containing gas (e.g., methane, H₂, etc.) emitted from the gasdistributor 150 is shown as gas bubbles 155 rising through the liquidsulfur 140. Above the internal heating system 180 and liquid sulfurlevel 145 is a quench column 190 that extends up to the liquid sulfurinlet 120 near the top of the H₂S reactor vessel 110.

The reaction chamber 115, the reactor wall 105, and the quench column190 in FIG. 1 generally can be cylindrical in shape, but othergeometries and orientations can be employed. For instance, as analternative to a circular cross-section (when viewed from above orbelow, such as from the gas outlet 170), the reaction chamber 115, thereactor wall 105, and the quench column 190 can have a rectangular,elliptical, or oval cross-section.

The reaction chamber 115, the reactor wall 105, the quench column 190,the gas distributor 150, and other surfaces within the H₂S reactorvessel 110 can be constructed of any suitable metal material, theselection of which can depend upon the desired operating temperature,desired operating pressure, and inertness to the reactor contents (e.g.,molten sulfur, H₂, gaseous H₂S), amongst other factors. Typical metalmaterials can include carbon steel, stainless steel, and the like. Insome embodiments, stainless steel can be used for such components.Moreover, a coating or layer containing any suitable material, compound,alloy, or metal can be used on any reactor surface (e.g., the reactionchamber 115, the gas distributor 150) to provide resistance to chemicalcorrosion.

The H₂S reactor vessel 110 and the reaction chamber 115 can beconfigured for operating temperatures of at least about 300° C. or atleast about 400° C., and in some embodiments, temperatures fallingwithin a range from about 300° C. to about 700° C., from about 350° C.to about 650° C., from about 400° C. to about 600° C., or from about425° C. to about 675° C. Likewise, the reactor vessel 110 and thereaction chamber 115 generally can be configured for operating pressuresof from about 2 to about 20 bars, from about 3 to about 15 bars, fromabout 5 to about 10 bars, from about 3 to about 8 bars, or from about 6to about 9 bars.

While not shown in FIG. 1, the reaction chamber 115 in the H₂S reactorvessel 110 can contain flow-affecting elements or baffles, which can beabove the gas distributor 150 or the internal heating system 180 andbelow the liquid sulfur level 145 during continuous operation, and thesecan increase the contact time between the gas bubbles 155 (e.g., H₂ ormethane) and the liquid sulfur 140. The gas distributor 150 can be ofany design suitable for adding or emitting or injecting gas, such as asparging pipe or device, or a plurality of nozzles. The gas inlet 130and the gas distributor 150 generally can be configured for gaspressures ranging from about 25 to about 200 psig, from about 50 toabout 150 psig, or from about 75 to about 125 psig.

Any suitable internal heating system 180 can be employed in the reactorvessel 110, so long as the system is capable of being used in a liquidsulfur environment and is capable of heating sulfur (and other reactorcontents) to a temperature of at least about 300° C. or at least about400° C., and maintaining typical operating temperatures ranging fromabout 300° C. to about 700° C., from about 350° C. to about 650° C.,from about 400° C. to about 600° C., or from about 425° C. to about 675°C. Often, the internal heating system 180 is an electric heating system,and the system can contain an electrical resistance heating element, anelectric heater tube bundle, as well as combinations thereof. In anembodiment of this invention, the reactor vessel does not containanother internal heating system other than the internal electricalheating system, for instance, the reactor vessel does not contain aninternal steam coil heating apparatus. Additionally, in anotherembodiment, the reactor vessel does not contain a heating jacket orsteam jacket on an exterior surface of the reactor vessel.

While not shown in FIG. 1, the quench column 190 can contain suitablepacking material, i.e., packing material that is inert to the reactorcontents. For example, the quench column can contain ceramic packing,Raschig rings, Pall rings, or similar materials. The quench column 190generally is configured to maintain a quench column operatingtemperature above the melting point of sulfur, for instance, at leastabout 120° C. or at least about 130° C. Quench column operatingtemperatures often can fall within a range from about 120° C. to about500° C., from about 125° C. to about 450° C., or from about 135° C. toabout 400° C., where lower temperatures are present at the top of thecolumn, and higher temperatures are present at the bottom of the column(and closer to the liquid sulfur 140).

Above the quench column 190 is the liquid sulfur inlet 120, in which thesulfur feed can be fresh liquid sulfur, recycled liquid sulfur, or amixture thereof. Sulfur exiting the bottom of the reactor vessel 110 atthe liquid sulfur outlet 160 can be connected with the liquid sulfurinlet 120, thereby forming a recycle or recirculation loop.

At the top of the H₂S reactor vessel 110 is the H₂S-rich gas outlet 170.For the reaction of sulfur with H₂ gas, generally this gas stream isH₂S-rich, with minimal or trace amounts of H₂ gas and/or sulfur vapor.For the reaction of sulfur with methane, generally this gas stream isH₂S-rich, with a lesser amount of CS₂. In an embodiment of thisinvention, the H₂S-rich gas stream existing the gas outlet 170 can havea purity of at least about 75 wt. % H₂S, at least about 90 wt. % H₂S, atleast about 95 wt. % H₂S, or at least about 98 wt. % H₂S. If desired,the H₂S-rich gas stream exiting the gas outlet 170 can be furtherprocessed and purified in a downstream separation system by removing atleast a portion of the sulfur vapor (optionally, trace H₂ may be removedas well), or by removing at least a portion of the CS₂, using anysuitable technique, such as condensation, distillation, or evaporation,as well as combination of these techniques.

Features, designs, and additional information on H₂S reactor vesselsthat can be employed in the H₂S reactor vessels with external heatingsystems described herein are disclosed in U.S. Pat. Nos. 2,214,859,2,857,250, 2,863,725, and 2,876,071, and European publication EP0339818, which are incorporated herein by reference in their entirety.

Referring now to FIG. 2, an exterior view of the bottom section of thereactor vessel of FIG. 1 is illustrated, showing a reaction chamber 215,a reactor wall 205, a liquid sulfur outlet 260, and a representativeliquid sulfur level 245. The parts labeled as 280 represent the externalconnections to the internal heating system, e.g., internal electricheater tube bundles. Above the internal heating system (with externalconnections 280) and below the liquid sulfur level 245 can beflow-affecting elements or baffles, similar to that describedhereinabove in relation to FIG. 1. A typical location for ahydrogen-containing gas inlet 230 for H₂ or methane, below the internalheating system, is shown in FIG. 2.

On the exterior of the reaction chamber 215 and reactor wall 205, andpositioned generally above and below the internal heating system (withexternal connections 280) is a portion of an external heating system285, discussed in greater detail hereinbelow.

Referring now to FIG. 3, a rotated exterior and close-up view of thebottom section of the reactor vessel of FIG. 1 is illustrated, showing areaction chamber 315, a reactor wall 305, and a liquid sulfur outlet360. The part labeled as 380 represents the external connection to theinternal heating system, e.g., internal electric heater tube bundles. Ahydrogen-containing gas inlet 330 for H₂ or methane, positioned belowthe internal heating system, is illustrated in FIG. 3.

On the exterior of the reaction chamber 315 and reactor wall 305, andpositioned generally above and below the internal heating system (withexternal connection 380) is a portion of an external heating system 385with a removable fastener 381, which are discussed in greater detailhereinbelow.

Referring now to FIG. 4, an exterior view of the top section of thereactor vessel of FIG. 1 is illustrated, showing a quench column 490, aliquid sulfur inlet 420, and a gas outlet 470. On the exterior of thequench column 490 are portions of an external heating system 485,discussed in greater detail hereinbelow.

FIG. 5 presents a close-up cross-sectional view of a portion of theexternal heating system generally represented in FIGS. 2-4. In FIG. 5,an exterior heating system 585 is adjacent an exterior surface of thereactor wall 505 of the reaction chamber 515. While not limited thereto,the exterior heating system 585 can include a heat transfer fluid 586contained within any suitable conduit, such as a pipe 584, which isconductively (but removably) attached to the reactor wall 505 with aheat transfer cement 583 or other similar material, such that heat fromthe heat transfer fluid 586 can flow to the reactor wall 505 and heat ormaintain the temperature of contents within the reaction chamber 515. Asshown in FIG. 5, sections of the conduit or pipe 584 that do notgenerally face the reactor wall 505 can be surrounded by insulation 587.An outer cover or plating 588 can cover the pipe 584, and can beremovable attached and/or banded to the reactor wall 505.

Consistent with embodiments of this invention (e.g., see FIGS. 2-3), theexternal heating system can comprise a heated reactor conduitconductively and removably attached to a portion of an exterior surfaceof the reactor wall, wherein at least a portion of the heated reactorconduit is positioned in close proximity to the internal heating systemand is configured to maintain a start-up temperature of the liquidsulfur above the melting point of sulfur at least until a level of theliquid sulfur in the reaction chamber is above the internal heatingsystem. Generally, the external heating system (and/or the heatedreactor conduit) can be configured to maintain the temperature of theliquid sulfur of at least about 120° C., or at least about 130° C., andtypically in a range from about 120° C. to about 200° C., from about130° C. to about 175° C., or from about 125° C. to about 150° C.

Additionally, the external heating system (see e.g., FIG. 4) can furthercomprise a heated column conduit conductively and removably attached toa portion of an exterior surface of the quench column, wherein theheated column conduit is configured to maintain a quench columnoperating temperature of the liquid sulfur in the quench column abovethe melting point of sulfur. The quench column operating temperature isabove the melting point of sulfur, and often greater than equal to about120° C., or greater than or equal to about 130° C. Illustrative rangesfor the quench column operating temperature include from about 120° C.to about 500° C., from about 125° C. to about 450° C., or from about135° C. to about 400° C., where lower temperatures are present at thetop of the column, and higher temperatures are present at the bottom ofthe column (and closer to the liquid sulfur in the reaction chamber).

The heated reactor conduit and the heated column conduit, independently,can be of any suitable geometric shape (or cross-section), such asgenerally cylindrical, a tube, or a pipe, although other geometries andorientations can be employed. A pipe 584 is illustrated in FIG. 5 as theconduit. Independently, each conduit can comprise or can be constructedof any suitable metal or conductive material, non-limiting examples ofwhich can include carbon steel, stainless steel, aluminum, copper, andthe like, and well as combinations of more than one of these materials.Again referring to FIG. 5, within the conduit (e.g., pipe 584), anysuitable heat transfer fluid 586, such as water or steam, can becirculated. To achieve the desired start-up and quench column operatingtemperatures above the melting point of sulfur, steam is typicallycirculated with the respective conduits.

As shown in FIGS. 2-4, each conduit can comprise vertical sectionsoriented substantially in the vertical direction; additionally oralternatively, each conduit can comprise horizontal sections orientedsubstantially in the horizontal direction. Regarding the horizontalsections, these sections can be arcuately shaped, for instance, totraverse exterior surfaces that are generally circular in shape. Asdiscussed herein, the reaction chamber, the reactor wall, and the quenchcolumn can be generally cylindrical in shape.

Although not limited thereto, the external heating system can comprisefrom 1 to 4 heated reactor conduits (also referred to as heatingcircuits or steam circuits). For instance, as can be envisioned in FIGS.2-3, the external heating system 285/385 can contain one contiguousheated reactor conduit with vertical and horizontal sections andappropriate bends/elbows therebetween, such that it traverses thereactor wall 205/305 in close proximity (above and below) the internalheating system 280/380. Thus, it is possible for the external heatingsystem to contain only 1 heated reactor conduit (one heating circuit orsteam circuit). As would be recognized by one of skill in the art, 2 ormore heated reactor conduits can be used, as needed, for the reactionchamber containing liquid sulfur.

Likewise, although not limited thereto, the external heating system cancomprise from 1 to 4 heated column conduits (again, also referred to asheating circuits or steam circuits). For instance, as can be envisionedin FIG. 4, the external heating system 485 can contain three separateheated column conduits, due to the sheer size of the quench column 490,although more or less contiguous conduits can be used as needed. Eachheated conduit can have vertical and horizontal sections and appropriatebends/elbows therebetween, such that it traverses the quench column asillustrated representatively in FIG. 4.

As shown in the FIG. 5, a suitable heat transfer material, such as aheat transfer cement 583, often a non-drying heat transfer cement, canbe present between the conduit (pipe 584) and the exterior surface ofthe reactor wall 505. Typically, this can be used to minimize air gapsand promote efficient heat transfer into the reactor vessel, but doesnot permanently affix the conduit to the reactor vessel, i.e., it isconductively and removably attached. Additionally, the external heatingsystem can further comprise insulation 587 adjacent at least a portionof the conduit, typically adjacent conduit surfaces that face away fromthe reactor vessel. Moreover, the external heating system can furthercomprise any suitable cover or plating 588 over the conduit (the heatedreactor conduit, the heated column conduit), as well as over theinsulation and heat transfer material/cement, if used. The cover orplating can be stainless steel, and can be configured to support theconduit and be removably attached to the exterior surface of the reactorvessel. In FIGS. 2-4, it is the cover or plating of the external heatingsystem 285/385/485 that is externally visible in these illustrations.The conduit/pipe, insulation, and heat transfer material/cement areunderneath the cover or plating in FIGS. 2-4, and their spatialrelationship is represented in FIG. 5.

The external heating system (and/or the cover, and/or the conduit) canbe removably supported about the respective exterior surface of thereactor vessel with any suitable removable fastener known to those ofskill in the art, non-limiting examples of which can include bolts,screws, metal bands, and the like, as well as combinations thereof. InFIG. 3, illustrated is a removable fastener 381 that supports theexternal heating system (inclusive of the cover and the conduit) aboutthe exterior surface of the reactor wall 305 and reaction chamber 315.

To facilitate ease of fastening, the exterior surface of the reactorvessel can further comprise any suitable attachment point known to thoseof skill in the art, non-limiting examples of which can includeprotrusions, knobs, brackets, and the like, as well as combinationsthereof. The attachment point can facilitate the removable connection(bolting onto, screwing onto, and the like) of the external heatingsystem (and/or the cover, and/or the conduit) onto the reactor vessel.

Beneficially, FIGS. 2-4 demonstrate that the heated reactor conduit andthe heated column conduit represent only a small fraction of theexterior surfaces of the reactor vessel. Thus, the external heatingsystem does not completely envelop vertical/horizontal exterior surfacesof the reactor vessel. For instance, the heated reactor conduit (and/orthe heated column conduit) can be positioned on less than about 33% ofthe surface area of the exterior surface of the reactor wall (and/or theexterior surface of the quench column), and in some embodiments, lessthan about 25% of the surface area, less than about 20% of the surfacearea, less than about 10% of the surface area, or less than about 5% ofthe surface area.

Also beneficially, the external heating system (and/or each heatedconduit) is capable of withstanding the thermal expansion andcontraction of stainless steel (e.g., used in the reaction chamber,reactor wall, and quench column) over an extremely robust temperaturerange, where temperature ranges can span at least about 300° C., atleast about 350° C., at least about 400° C., or at least about 500° C.In an embodiment, for example, the external heating system (and/or eachheated conduit) is capable of withstanding the thermal expansion andcontraction of stainless steel over a temperature range from a firsttemperature of about 25° C. to a second temperature of about 650° C.;alternatively, from a first temperature of about 25° C. to a secondtemperature of about 500° C.; alternatively, from a first temperature ofabout 125° C. to a second temperature of about 675° C.; oralternatively, from a first temperature of about 125° C. to a secondtemperature of about 525° C.

While the design or layout of the external heating system (and/or thecover) is not altogether limiting, other than not covering the entiretyof the horizontal exterior surface or vertical exterior surface, thedesign or layout depicted herein often can be described as a cage-likeappearance, a grid-like appearance, a frame-like appearance, or alattice-like appearance, among other descriptions.

Hydrogen Sulfide Production Processes

Embodiments of this invention also are directed to H₂S productionprocesses. Such processes can comprise, consist essentially of, orconsist of (i) controlling a reaction chamber containing liquid sulfurat a start-up temperature above the melting point of sulfur with anexternal heating system comprising a heated reactor conduit conductivelyand removably attached to an exterior surface of the reaction chamber;(ii) adding liquid sulfur to the reaction chamber to a level sufficientto immerse an internal heating system positioned within the reactionchamber; (iii) engaging the internal heating system to reach andmaintain an operating temperature of the liquid sulfur of at least about300° C. (e.g., ranging from 425 to 525° C.); (iv) adding ahydrogen-containing gas into the liquid sulfur and reacting to produceH₂S; and (v) optionally, discontinuing the operation of the externalheating system. Generally, the features of these processes (e.g., thestart-up temperature, the external heating system, the internal heatingsystem, the operating temperature, and the hydrogen-containing gas,among others) are independently described herein and these features canbe combined in any combination to further describe the disclosed H₂Sproduction processes. Moreover, other process steps can be conductedbefore, during, and/or after any of the steps listed in the disclosedprocesses, unless stated otherwise.

In one embodiment of this invention, the H₂S production process can be aprocess to produce H₂S from sulfur and H₂ gas (the hydrogen-containinggas), such as the Girdler process. In another embodiment, the H₂Sproduction process can be a process to produce H₂S (and CS₂) from sulfurand methane (the hydrogen-containing gas). In these and otherembodiments, the process can include a catalyst or, alternatively, theprocess does not include a catalyst.

Consistent with embodiments disclosed herein, step (i) of the processrelates to controlling a reaction chamber containing liquid sulfur at astart-up temperature above the melting point of sulfur with an externalheating system comprising a heated reactor conduit conductively andremovably attached to an exterior surface of the reaction chamber. Thestandard melt point of sulfur is approximately 115.2° C. Therefore, thereaction chamber containing liquid sulfur can be controlled at astart-up temperature of at least about 116° C., at least about 120° C.,or at least about 130° C. Often, the start-up temperature can be in arange from about 120° C. to about 200° C., from about 130° C. to about200° C., from about 130° C. to about 175° C., or from about 125° C. toabout 150° C.

In step (ii), liquid sulfur is added to the reaction chamber to a levelsufficient to immerse the internal heating system positioned within thereaction chamber (see FIG. 1). It is customary practice to engage theinternal heating system only after the heating system is fully immersedin the liquid sulfur.

The internal heating system is engaged in step (iii) to reach andmaintain an operating temperature of the liquid sulfur of at least about300° C., or at least about 400° C. Often, the operating temperatureduring steady-state operation can range from about 300° C. to about 700°C., from about 350° C. to about 600° C., from about 400° C. to about600° C., from about 425° C. to about 675° C., or from about 425° C. toabout 550° C. While not being limited thereto, typical steady-stateoperating pressures can fall within a range from about 2 to about 20bars, from about 3 to about 15 bars, from about 5 to about 10 bars, fromabout 3 to about 8 bars, or from about 6 to about 9 bars.

The internal heating system in step (iii) is described hereinabove, andcan be any suitable internal electric heating system comprising, forinstance, an electrical resistance heating element, an electric heatertube bundle, or combinations thereof. Generally, the process does notrequire or employ an internal steam coil heating apparatus or a heatingjacket or steam jacket on the exterior surface of the reaction chamber.

In step (iv), the hydrogen-containing gas—such as methane or H₂, and thelike—is added or injected into the liquid sulfur, and reacted to produceH₂S. Any suitable hydrogen-containing gas pressure can be used.Illustrative and non-limiting pressure ranges include from about 25 toabout 200 psig, from about 50 to about 150 psig, or from about 75 toabout 125 psig.

The processes of this invention generally are capable of producing H₂Shaving a purity of at least about 75 wt. % H₂S, and in some embodiments,at least about 90 wt. % H₂S, at least about 95 wt. % H₂S, or at leastabout 98 wt. % H₂S. Moreover, the process can further comprise a step ofisolating/purifying the H₂S by removing at least a portion of CS₂ (e.g.,if methane is a reactant), and/or at least a portion of H₂ (e.g., ifneeded, and if H₂ is a reactant), and/or at least a portion of sulfurvapor, from the H₂S. This can be accomplished using any suitable,including condensation, distillation, or evaporation, as well ascombinations of more than one of these techniques.

In step (v), the operation of the external heating system, which isdescribed in detail hereinabove, can be discontinued. Generally, oncethe internal heating system is fully engaged at the desired operatingtemperature, it is not necessary to continue the use of the externalheating system. Therefore, in such circumstances, the operation of theexternal heating system is discontinued.

The invention is described above with reference to numerous aspects andembodiments, and specific examples. Many variations will suggestthemselves to those skilled in the art in light of the above detaileddescription. All such obvious variations are within the full intendedscope of the appended claims. Other embodiments of the invention caninclude, but are not limited to, the following (embodiments aredescribed as “comprising” but, alternatively, can “consist essentiallyof” or “consist of”):

Embodiment 1. A H₂S reactor vessel comprising:

(a) a reaction chamber comprising a reactor wall, the reaction chamberconfigured to contain liquid sulfur;

(b) a reactor inlet for liquid sulfur, the reactor inlet positioned atan upper portion of the reactor vessel;

(c) a reactor outlet for liquid sulfur, the reactor outlet positioned ata lower portion of the reactor vessel;

(d) a gas inlet for a hydrogen-containing gas, the gas inlet connectedto a gas distributor, the gas distributor positioned above the reactoroutlet for liquid sulfur and configured to inject thehydrogen-containing gas into the liquid sulfur in the reaction chamber;

(e) a gas outlet for a H₂S-rich gas stream, the gas outlet positionedabove the reactor inlet;

(f) an internal heating system, the internal heating system positionedin the liquid sulfur in the reaction chamber during continuous operationof the reactor vessel and configured to maintain an operatingtemperature above the melting point of sulfur; and

(g) an external heating system comprising a heated reactor conduit (oneor a plurality of heated reactor conduits) conductively and removablyattached to a portion of an exterior surface of the reactor wall,wherein at least a portion of the heated reactor conduit is positionedin close proximity to the internal heating system and is configured tomaintain a start-up temperature of the liquid sulfur above the meltingpoint of sulfur at least until a level of the liquid sulfur in thereaction chamber is above the internal heating system.

Embodiment 2. The vessel defined in embodiment 1, wherein the reactorvessel (and/or the reaction chamber) is configured for an operatingtemperature in any suitable range or in any range disclosed herein,e.g., at least about 300° C., at least about 400° C., from about 300° C.to about 700° C., from about 350° C. to about 650° C., from about 400°C. to about 600° C., or from about 425° C. to about 675° C.

Embodiment 3. The vessel defined in embodiment 1 or 2, wherein thereactor vessel (and/or the reaction chamber) is configured for anoperating pressure in any suitable range or in any range disclosedherein, e.g., from about 2 to about 20 bars, from about 3 to about 15bars, from about 3 to about 8 bars, or from about 6 to about 9 bars.

Embodiment 4. The vessel defined in any one of the precedingembodiments, wherein the reactor inlet is configured for fresh liquidsulfur, recycled liquid sulfur, or a mixture thereof.

Embodiment 5. The vessel defined in any one of the precedingembodiments, wherein the reactor inlet and the reactor outlet areconnected to form a recycle loop for liquid sulfur.

Embodiment 6. The vessel defined in any one of the precedingembodiments, wherein the gas inlet (and/or the gas distributor) isconfigured for any suitable hydrogen-containing gas (e.g., methane, H₂,etc.) at a pressure in any suitable range or in any range disclosedherein, e.g., from about 25 to about 200 psig, from about 50 to about150 psig, or from about 75 to about 125 psig.

Embodiment 7. The vessel defined in any one of the precedingembodiments, wherein the gas distributor comprises any suitable gasdistributor or any gas distributor disclosed herein, e.g., a pluralityof nozzles, or a sparging pipe or device.

Embodiment 8. The vessel defined in any one of the precedingembodiments, wherein the H₂S-rich gas stream comprises H₂S, H₂, andsulfur vapor or comprises H₂S and CS₂.

Embodiment 9. The vessel defined in any one of the precedingembodiments, wherein the reactor vessel (and/or the gas outlet) isconfigured to provide a H₂S-rich gas stream having a purity of at leastabout 75 wt. % H₂S, at least about 90 wt. % H₂S, at least about 95 wt. %H₂S, or at least about 98 wt. % H₂S.

Embodiment 10. The vessel defined in any one of the precedingembodiments, further comprising a downstream separation system connectedto the gas outlet, the downstream separation system configured to purifythe H₂S-rich gas stream by removing at least a portion of the sulfurvapor using any suitable technique or any technique disclosed herein,e.g., condensation, distillation, or evaporation, as well ascombinations thereof.

Embodiment 11. The vessel defined in any one of the precedingembodiments, wherein the reaction chamber further comprisesflow-affecting elements (e.g., baffles) to increase contact between thehydrogen-containing gas and the liquid sulfur, and the flow-affectingelements can be positioned in any suitable location (e.g., above the gasdistributor and below the level of the liquid sulfur during continuousoperation).

Embodiment 12. The vessel defined in any one of the precedingembodiments, wherein the reactor vessel (and/or the reaction chamber) isconfigured to produce H₂S from H₂ gas and liquid sulfur (e.g., theGirdler process) and/or to produce H₂S from methane and sulfur.

Embodiment 13. The vessel defined in any one of the precedingembodiments, wherein the reactor vessel (and/or the reaction chamber)does not contain a catalyst.

Embodiment 14. The vessel defined in any one of the precedingembodiments, wherein the internal heating system is further configuredto heat sulfur from at or near the melting point of sulfur to anoperating temperature (and maintain the operating temperature) in anysuitable range or in any range disclosed herein, e.g., at least about300° C., at least about 400° C., from about 300° C. to about 700° C.,from about 350° C. to about 650° C., from about 400° C. to about 600°C., or from about 425° C. to about 675° C.

Embodiment 15. The vessel defined in any one of the precedingembodiments, wherein the internal heating system is any suitableelectric heating system or any electric heating system disclosed herein,e.g., an electrical resistance heating element, an electric heater tubebundle, or a combination thereof.

Embodiment 16. The vessel defined in any one of the precedingembodiments, wherein the reactor vessel does not contain anotherinternal heating system other than the internal electrical heatingsystem, e.g., the reactor vessel does not contain an internal steam coilheating apparatus.

Embodiment 17. The vessel defined in any one of the precedingembodiments, wherein the reactor vessel does not contain a heatingjacket or steam jacket on an exterior surface of the reactor vessel.

Embodiment 18. The vessel defined in any one of the precedingembodiments, wherein the reactor vessel further comprises a quenchcolumn positioned above the internal heating system (and/or the level ofthe liquid sulfur) and below the reactor inlet for liquid sulfur.

Embodiment 19. The vessel defined in embodiment 18, wherein the quenchcolumn is configured to maintain a quench column operating temperatureabove the melting point of sulfur, and the quench column operatingtemperature is in any suitable range or in any range disclosed herein,e.g., at least about 120° C., at least about 130° C., from about 120° C.to about 500° C., from about 125° C. to about 450° C., or from about135° C. to about 400° C.

Embodiment 20. The vessel defined in embodiment 18 or 19, wherein thequench column contains any suitable inert packing material or any inertpacking material disclosed herein, e.g., ceramic packing, Raschig rings,or Pall Rings, as well as combinations thereof.

Embodiment 21. The vessel defined in any one of the precedingembodiments, wherein the reaction chamber (and/or the quench column) hasa generally cylindrical shape.

Embodiment 22. The vessel defined in any one of the precedingembodiments, wherein the reactor vessel (and/or the reaction chamber,and/or the reactor wall, and/or the quench column) comprises (or isconstructed of) any suitable metal material, or any metal materialdisclosed herein, e.g., stainless steel.

Embodiment 23. The vessel defined in any one of the precedingembodiments, wherein the reactor vessel (and/or the reaction chamber,and/or the reactor wall, and/or the quench column) comprises acoating/layer comprising any suitable material that provides resistanceto corrosion.

Embodiment 24. The vessel defined in any one of the precedingembodiments, wherein the external heating system (and/or the reactorconduit) is configured to maintain a start-up temperature of the liquidsulfur in any suitable range or in any range disclosed herein, e.g., atleast about 120° C., at least about 130 ° C., from about 120° C. toabout 200° C., from about 130° C. to about 175° C., or from about 125°C. to about 150° C.

Embodiment 25. The vessel defined in any one of the precedingembodiments, wherein the external heating system further comprises aheated column conduit conductively and removably attached to at least aportion of an exterior surface of the quench column, wherein the heatedcolumn conduit is configured to maintain a quench column operatingtemperature of the liquid sulfur in the quench column above the meltingpoint of sulfur.

Embodiment 26. The vessel defined in embodiment 25, wherein the quenchcolumn operating temperature is above the melting point of sulfur, andthe quench column operating temperature is in any suitable range or inany range disclosed herein, e.g., at least about 120° C., at least about130° C., from about 120° C. to about 500° C., from about 125° C. toabout 450° C., or from about 135° C. to about 400° C.

Embodiment 27. The vessel defined in any one of the precedingembodiments, wherein each conduit is of any suitable geometric shape (orcross-section) or any geometric shape (or cross-section) disclosedherein, e.g., generally cylindrical, a tube, or a pipe.

Embodiment 28. The vessel defined in any one of the precedingembodiments, wherein each conduit comprises (or is constructed of) anysuitable conductive material, or any conductive material disclosedherein, e.g., carbon steel, stainless steel, aluminum, copper, orcombinations thereof.

Embodiment 29. The vessel defined in any one of the precedingembodiments, wherein any suitable heat transfer fluid or any heattransfer fluid disclosed herein (e.g., water or steam) is circulated ineach conduit.

Embodiment 30. The vessel defined in any one of the precedingembodiments, wherein each conduit comprises vertical sections orientedsubstantially in the vertical direction.

Embodiment 31. The vessel defined in any one of the precedingembodiments, wherein each conduit comprises horizontal sections orientedsubstantially in the horizontal direction.

Embodiment 32. The vessel defined in embodiment 31, wherein thehorizontal sections are arcuately shaped, e.g., to traverse exteriorsurfaces that are generally circular in shape.

Embodiment 33. The vessel defined in any one of the precedingembodiments, wherein the external heating system comprises from 1 to 4heated reactor conduits and/or from 1 to 4 heated column conduits.

Embodiment 34. The vessel defined in any one of the precedingembodiments, wherein any suitable heat transfer material or any heattransfer material disclosed herein (e.g., a heat transfer cement,non-drying) is present between each conduit and the exterior surface tominimize air gaps and promote efficient heat transfer.

Embodiment 35. The vessel defined in any one of the precedingembodiments, wherein the external heating system (and/or each heatedconduit) is capable of withstanding the thermal expansion andcontraction of stainless steel (e.g., reaction chamber or reactor wall)over any suitable temperature range or any range disclosed herein, e.g.,a temperature range of at least about 300° C., or at least about 350°C.; from a first temperature of about 25° C. to a second temperature ofabout 650° C., from a first temperature of about 25° C. to a secondtemperature of about 500° C., from a first temperature of about 125° C.to a second temperature of about 675° C., or from a first temperature ofabout 125° C. to a second temperature of about 525° C.

Embodiment 36. The vessel defined in any one of the precedingembodiments, wherein the heated reactor conduit (and/or the heatedcolumn conduit) is positioned on a minor fraction of the exteriorsurface of the reactor wall (and/or the exterior surface of the quenchcolumn), e.g., less than about 33% of the surface area, less than about25% of the surface area, less than about 20% of the surface area, lessthan about 10% of the surface area, or less than about 5% of the surfacearea.

Embodiment 37. The vessel defined in any one of the precedingembodiments, wherein the external heating system further comprisesinsulation adjacent at least a portion of each conduit facing away fromthe exterior surface.

Embodiment 38. The vessel defined in any one of the precedingembodiments, wherein the external heating system further comprising anysuitable cover over the heated reactor conduit and/or the heated columnconduit (and/or the insulation, and/or the heat transfer material) orany cover disclosed herein, e.g., a stainless steel cover, the coverconfigured to be removably attached to the exterior surface of thereactor vessel.

Embodiment 39. The vessel defined in any one of the precedingembodiments, wherein the external heating system (and/or the cover,and/or the conduit) is removably supported about the exterior surfacewith any suitable removable fastener or any removable fastener disclosedherein, e.g., a bolt, a screw, a metal band, or combinations thereof.

Embodiment 40. The vessel defined in any one of the precedingembodiments, wherein the exterior surface has any suitable attachmentpoint or any attachment point disclosed herein (e.g., a protrusion, aknob, a bracket, or combinations thereof) to facilitate the removableconnection (bolting onto, screwing onto, and the like) of the externalheating system (and/or the cover, and/or the conduit).

Embodiment 41. The vessel defined in any one of the precedingembodiments, wherein the external heating system (and/or the cover)comprises any suitable design or layout that does not cover the entiretyof the exterior horizontal surface or the exterior vertical surface, orany design or layout disclosed herein, e.g., a cage-like appearance, agrid-like appearance, a frame-like appearance, or a lattice-likeappearance.

Embodiment 42. A H₂S production process comprising:

(i) controlling a reaction chamber containing liquid sulfur at astart-up temperature above the melting point of sulfur with an externalheating system comprising a heated reactor conduit conductively andremovably attached to an exterior surface of the reaction chamber;

(ii) adding liquid sulfur to the reaction chamber to a level sufficientto immerse an internal heating system positioned within the reactionchamber;

(iii) engaging the internal heating system to reach and maintain anoperating temperature of the liquid sulfur of at least about 300° C.;

(iv) adding a hydrogen-containing gas into the liquid sulfur andreacting to produce H₂S; and

(v) optionally, discontinuing the operation of the external heatingsystem.

Embodiment 43. The process defined in embodiment 42, wherein theoperating temperature is in any suitable range or in any range disclosedherein, e.g., at least about 400° C., from about 300° C. to about 700°C., from about 350° C. to about 600° C., from about 400° C. to about600° C., or from about 425° C. to about 675° C.

Embodiment 44. The process defined in embodiment 42 or 43, wherein thestart-up temperature is in any suitable range or in any range disclosedherein, e.g., at least about 116° C., at least about 120° C., from about120° C. to about 200° C., from about 130° C. to about 200° C., fromabout 130° C. to about 175° C., or from about 125° C. to about 150° C.

Embodiment 45. The process defined in any one of embodiments 42-44,wherein the reacting in step (iv) is conducted at an operating pressurein any suitable range or in any range disclosed herein, e.g., from about2 to about 20 bars, from about 3 to about 15 bars, from about 3 to about8 bars, or from about 6 to about 9 bars.

Embodiment 46. The process defined in any one of embodiments 42-45,wherein the adding in step (iv) is conducted with a hydrogen-containinggas (e.g., methane, H₂, etc.) at a gas pressure in any suitable range orin any range disclosed herein, e.g., from about 25 to about 200 psig,from about 50 to about 150 psig, or from about 75 to about 125 psig.

Embodiment 47. The process defined in any one of embodiments 42-46,wherein H₂S is produced at a purity of at least about 75 wt. % H₂S, atleast about 90 wt. % H₂S, at least about 95 wt. % H₂S, or at least about98 wt. % H₂S.

Embodiment 48. The process defined in any one of embodiments 42-47,further comprising a step of isolating/purifying the H₂S by removing atleast a portion of CS₂, and/or at least a portion of H₂ and/or at leasta portion of sulfur vapor, from the H₂S using any suitable technique orany technique disclosed herein, e.g., condensation, distillation, orevaporation, as well as combinations thereof.

Embodiment 49. The process defined in any one of embodiments 42-48,wherein the process does not include a catalyst.

Embodiment 50. The process defined in any one of embodiments 42-49,wherein the internal heating system is any suitable electric heatingsystem or any electric heating system disclosed herein, e.g., anelectrical resistance heating element, an electric heater tube bundle,or a combination thereof.

Embodiment 51. The process defined in any one of embodiments 42-50,wherein the process does not employ an internal steam coil heatingapparatus or a heating jacket or steam jacket on the exterior surface ofthe reaction chamber.

Embodiment 52. The process defined in any one of embodiments 42-51,wherein the process comprises discontinuing the operation of theexternal heating system in step (v).

Embodiment 53. The process defined in any one of embodiments 42-52,wherein the external heating system (and/or each heated conduit) isfurther defined in any one of embodiments 24-41.

We claim:
 1. A H₂S reactor vessel comprising: (a) a reaction chambercomprising a reactor wall, the reaction chamber configured to containliquid sulfur; (b) a reactor inlet for liquid sulfur, the reactor inletpositioned at an upper portion of the reactor vessel; (c) a reactoroutlet for liquid sulfur, the reactor outlet positioned at a lowerportion of the reactor vessel; (d) a gas inlet for a hydrogen-containinggas, the gas inlet connected to a gas distributor, the gas distributorpositioned above the reactor outlet for liquid sulfur and configured toinject the hydrogen-containing gas into the liquid sulfur in thereaction chamber; (e) a gas outlet for a H₂S-rich gas stream, the gasoutlet positioned above the reactor inlet; (f) an internal heatingsystem, the internal heating system positioned in the liquid sulfur inthe reaction chamber during continuous operation of the reactor vesseland configured to maintain an operating temperature above the meltingpoint of sulfur; (g) an external heating system comprising a heatedreactor conduit conductively and removably attached to a portion of anexterior surface of the reactor wall, wherein at least a portion of theheated reactor conduit is positioned in close proximity to the internalheating system and is configured to maintain a start-up temperature ofthe liquid sulfur above the melting point of sulfur at least until alevel of the liquid sulfur in the reaction chamber is above the internalheating system; and (h) a quench column positioned above the internalheating system and below the reactor inlet; wherein: the externalheating system further comprises a heated column conduit conductivelyand removably attached to at least a portion of an exterior surface ofthe quench column, wherein the heated column conduit is configured tomaintain a quench column operating temperature of the liquid sulfur inthe quench column above the melting point of sulfur; and the quenchcolumn operating temperature is at least about 120° C.
 2. The vessel ofclaim 1, wherein the reactor vessel is configured for an operatingtemperature of at least about 300° C.
 3. The vessel of claim 1, whereinthe hydrogen-containing gas comprises H₂.
 4. The vessel of claim 1,wherein the reactor vessel is configured to produce a H₂S-rich gasstream comprising at least about 95 wt. % H₂S.
 5. The vessel of claim 1,wherein the internal heating system is an electric heating systemconfigured to maintain an operating temperature of at least about 400°C.
 6. The vessel of claim 1, wherein the external heating system isconfigured to maintain a start-up temperature of at least about 120° C.7. The vessel of claim 1, wherein the heated reactor conduit comprisessteam circulating through a pipe constructed of a conductive metalmaterial.
 8. The vessel of claim 1, wherein the external heating systemcomprises from 1 to 4 heated reactor conduits.
 9. The vessel of claim 1,wherein a heat transfer material is present between the heated reactorconduit and the exterior surface of the reactor wall.
 10. The vessel ofclaim 1, wherein the reactor vessel comprises stainless steel, and theexternal heating system is capable of withstanding the thermal expansionand contraction of stainless steel over a temperature range of at leastabout 350° C.
 11. The vessel of claim 1, wherein the heated reactorconduit is present on less than about 10% of the surface area of theexterior surface of the reactor wall.
 12. The vessel of claim 1, whereinthe external heating system comprises a cover over the heated reactorconduit, the cover configured to be removably attached to the exteriorsurface of the reactor wall.
 13. The vessel of claim 12, wherein theexterior surface of the reactor wall further comprises an attachmentpoint configured for the removable attachment of the cover.
 14. Thevessel of claim 12, wherein the heated reactor conduit and the cover areremovably supported about the exterior surface of the reactor wall witha fastener.
 15. The vessel of claim 1, wherein the heated column conduitis present on less than about 20% of the surface area of the exteriorsurface of the quench column.
 16. The vessel of claim 1, wherein theexternal heating system comprises from 1 to 4 heated column conduits.17. The vessel of claim 1, wherein the quench column operatingtemperature is in a range from about 125° C. to about 450° C.
 18. Thevessel of claim 1, wherein the heated column conduit comprises steamcirculating through a pipe constructed of a conductive metal material.19. The vessel of claim 1, wherein a heat transfer material is presentbetween the heated column conduit and the exterior surface of the quenchcolumn.
 20. The vessel of claim 1, wherein the external heating systemcomprises a cover over the heated column conduit, the cover configuredto be removably attached to the exterior surface of the quench column.21. The vessel of claim 20, wherein the exterior surface of the quenchcolumn further comprises an attachment point configured for theremovable attachment of the cover.
 22. The vessel of claim 20, whereinthe heated column conduit and the cover are removably supported aboutthe exterior surface of the quench column with a fastener.